Reference library

Dictionaries & sets

Key–value maps, uniqueness, counting, grouping, and fast lookups.

3 matches
Dictionaries & sets easy

How to Merge Dictionaries and Find Unique Keys in Python

Merge two dictionaries with update(), then use sets to find all unique keys and the keys shared between both dictionaries.

dictionaries sets merge
Python
def merge_and_unique(dict1, dict2):
    merged = dict1.copy()
    merged.update(dict2)
    unique_keys = set(merged.keys())
    common_keys = set(dict1.keys()) & set(dict2.keys())
    return merged, unique_keys, common_keys


if __name__ == "__main__":
    fruits = {"apple": 3, "banana": 5, "orange": 2}
    more_fruit…
14 0 Open
Dictionaries & sets easy

How to Merge Two Dictionaries in Python with the Spread Operator

Merge two Python dictionaries into one new dict using the ** unpacking (spread) operator, with later keys overriding earlier ones.

dicts merge spread-operator
Python
def merge_two_dicts(dict1: dict, dict2: dict) -> dict:
    """Merge two dictionaries using the spread operator pattern."""
    # The ** operator unpacks key-value pairs, later keys overwrite earlier ones
    merged = {**dict1, **dict2}
    return merged


if __name__ == "__main__":
    # Example usage with overlapping…
15 0 Open
Dictionaries & sets easy

How to merge dictionaries and sets in Python

Merges multiple dictionaries with the ** unpacking operator and combines sets using union operations into a single structure.

dict-merge set-union unpacking
Python
def merge_dictionaries_and_sets(school_dict, teacher_dict, course_dict, student_sets):
    """
    Merges multiple dictionaries and sets into a single combined structure.
    Demonstrates dict unpacking and set union operations.
    """
    # Merge all dictionaries using the unpacking operator (Python 3.9+)
    merged…
12 0 Open

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